So… either settle back in your favourite chair with a coffee, and let’s see where we go on today’s Sunday Run, or… put this aside, fire-up the Harley and cruise around the backroads! Then come back and read our story in the quiet of the afternoon.
If we asked ten Harley-Davidson enthusiasts or owners “which is the most significant Harley ever made?”, we’d probably get ten different answers! But note that the question asks for “most significant”, not ‘favourite’, not ‘best’… but the one that maybe saved the Motor Company, or the one that changed the motorcycling world through brilliance and innovation.
We have two models which we believe are the most significant. In second place, the 1984 Softail. In first place… the 1936 EL Knucklehead. It’s nearly a tied result, but the fact that some sections of the Softail were styled to emulate the look of the EL gives primacy to the older bike. The 1936 EL is without doubt one of the most influential models ever released by Harley-Davidson Motor Company. It’s a milestone motorcycle and one of the most important American bikes ever made.
How special is a 1936 EL today to a collector? Price in 1936 US dollars: $380. Price now in USD if you can find one: a pristine EL was auctioned for USD$190,000. We’ve spoken before about Harleys being “where engineering meets art”, and the EL is an example of how this union can work perfectly. Let’s begin with the engineering.
The all-new engine – later known as the Knucklehead - in the 1936 EL was the first Harley with overhead valves, and the first with re-circulating oil pump lubrication.
Let’s get to that name “Knucklehead” before we go much further… make a fist, and hold it up with the back of your hand in front of your eyes. Your knuckles are the polished rocker arm nuts, with the tendons on your hand are the pushrod tubes.
The move to overhead valves was aimed at retail customers, and (no surprise here) horsepower! The original conceptual design was by William Harley himself (one of the four founders), and was given to engineers Hank Syvertson and Joe Petrali to hammer out the details to create a commercially viable overhead valve V-twin engine.
The two innovations we mentioned - overhead valves, and re-circulating oil pump lubrication – go hand in hand. Until 1930 H-D had used side-valve designs in the V-Twins, and the 1930 release of an inlet-over-exhaust engine in the VL models. It was a problem engine, so much so that as early as 1931 the Motor Company began work on a sumped-oiling engine.
(Just for interest, oiling systems up to then had been “total loss” oiling, oil was pumped through the engine, dripped or sprayed onto the valve gear, and either burned or pumped out and dumped.)
Sumped oiling was by then common in cars, but rare in motorcycles, and H-D was aware that the “enemy” Indian Motorcycle Co was developing a dry-sump (oil in separate tank) re-circulating lubrication system for its side-valve twins.
But the Harley engineers went a step further, and worked on a dry-sump oil system and overhead valves.
There’s another vital reason behind the development of the 1936 EL… the Great Depression. By 1932, it was affecting businesses all over America, and Harley sales, almost 24,000 bikes in 1929, had decreased to 7,213 motorcycles over the 1932 model year. Sales hit the bottom in 1933, down to about 3,700 bikes. However, the overhead valve project continued to move along. Harley’s plan was to build a fast and reliable bike that could be used every day by ordinary riders, with reliability being the major and key goal. So the OHV Knucklehead and EL program progressed!
At the annual Harley-Davidson dealers convention in November 1935, Walter Davidson and William Harley raised the curtain on the new 61-cubic-inch (1000cc) overhead valve machine “to cheers and applause”.
The overhead valves and oiling were not the only feature of the new model, which came in two versions: the standard E model with 6.5:1 compression and the EL sport version with 7:1 compression. The low compression ratios reflected the poor quality and consistency of petrol at that time, and were also intended to not put too much stress on the untried bottom end (remember it was an all-new engine! And also remember that the bottom-end proved to be tough enough to remain pretty much un-changed until the end of the Evolution engines in 1999!).
The engine also featured a new clutch, the gearbox was a 4-speed (replacing a 3-speed) with constant mesh, unlike Harley-Davidson’s competition Indian, who’s gearbox had straight cut gears in an old fashioned “crash box”, and as we said, dry-sump lubrication with the oil carried in a separate tank instead of in a section of the fuel tank, as it was on earlier models.
The four cam lobes spun on a single camshaft, aiding accurate valve timing. Claimed horsepower of the EL sport model was 40 horsepower at 4,800rpm.
And now, let’s visit the “Art” aspect of the “engineering and art” story.
The styling, pure Art Deco, matched the entire 1930s ethos (as the world came out of the depression) of “movement towards the future”. Everything new… ocean liners, trains, cars, and now motorcycles… looked to a new, better, faster world. The EL was beautifully styled for the era, and today remains a stunning example of mechanical simplicity and art.
The forks were new, smooth extruded tubular forks. The frame was new… check the photos here and note the straight-line from the steering head to the rear axle. Still used today.
Admire the teardrop fuel tank profile, new on the EL… still used today. Check the horseshoe oil tank… still used today, at least as a visual cue. See the instrument panel on top of the tank – a new idea in 1936 - artistically executed, and still used today.
The bike’s lines flowed smoothly from the curving front fender to the pointed taillight, with no “air-gaps” in the profile. Standard two-tone paint combinations again lifted the Motor Company’s products above and ahead of the competition.
For 1937, Harley also continued building its 45-, 74- and 80-cubic-inch sidevalve models, but they were restyled to look like the newer EL overhead valve models. And in the 1937 model year sales were up to 11,674 motorcycles.
Harley-Davidson had survived some very tough times, as it would do again and again over the decades, leading up to the full 123 year history of today.
So, the bottom line is this: Creating and launching the EL Knucklehead was a move of foresight and bravery from Harley-Davidson. Without the 1936 EL, there would be no 1984 Softail, no 1971 Super Glide, and the motorcycling world would not be what it is today.
Have a great Sunday!